Change targetSdk to Android 10, cut release v2.9

- Update versionCode & versionName for Google Play Store

- Set targetSDK to Android 10 / API level 29 / Android Q
  - https://source.android.com/setup/start/build-numbers
  - https://support.google.com/googleplay/android-developer/answer/113469#targetsdk

- Clean up IntentHelper by removing needless functions

- Clean up strings in debug messages & add missing ones

- Replace String.format() w/ template literals

- Upgrade to Kotlin 1.4

- Upgrade most dependencies

app/build.gradle

@@ -19,14 +19,14 @@ apply plugin: 'kotlin-android'
 apply plugin: 'kotlin-android-extensions'
 
 android {
-  compileSdkVersion 28
+  compileSdkVersion 29
   defaultConfig {
     applicationId "com.r3bl.stayawake"
     minSdkVersion 25
-    targetSdkVersion 28
+    targetSdkVersion 29
     // Update versionCode & versionName before adding a release to the Google Play Store.
-    versionCode 20
-    versionName "2.8"
+    versionCode 21
+    versionName "2.9"
   }
   buildTypes {
     release {
@@ -40,9 +40,9 @@ android {
 }
 
 dependencies {
-  implementation 'androidx.appcompat:appcompat:1.3.0-alpha01'
+  implementation 'androidx.appcompat:appcompat:1.3.0-alpha02'
   implementation 'junit:junit:4.13'
-  implementation "androidx.core:core-ktx:1.3.0"
+  implementation "androidx.core:core-ktx:1.3.1"
   implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"
   implementation 'org.greenrobot:eventbus:3.2.0'
 }

app/src/main/java/com/r3bl/stayawake/MyIntentBuilder.kt

@@ -86,11 +86,16 @@ fun buildIntent(block: MyIntentBuilder.() -> Unit): Intent = MyIntentBuilder().a
 // Intent helpers.
 class IntentHelper {
   companion object {
-    fun containsCommand(intent: Intent): Boolean = intent.extras.containsKey(Keys.CommandId.name)
-    fun containsMessage(intent: Intent): Boolean = intent.extras.containsKey(Keys.Message.name)
-
     @CommandId
-    fun getCommand(intent: Intent): Int = intent.extras.getInt(Keys.CommandId.name)
-    fun getMessage(intent: Intent): String = intent.extras.getString(Keys.Message.name)
+    fun getCommandId(intent: Intent): Int = intent.extras?.getInt(Keys.CommandId.name) ?: INVALID
+    fun getCommandIdDebugString(intent: Intent): String = when (getCommandId(intent)) {
+      INVALID -> "INVALID"
+      STOP    -> "STOP"
+      START   -> "START"
+      else    -> "UNKNOWN 🤔"
+    }
+
+    fun getMessage(intent: Intent): String? = intent.extras?.getString(Keys.Message.name)
+    fun getMessageDebugString(intent: Intent): String = getMessage(intent) ?: "N/A"
   }
 }